package com.atguigu.springcloud.lb.impl;

import com.atguigu.springcloud.lb.LoadBalancer;
import org.springframework.cloud.client.ServiceInstance;
import org.springframework.stereotype.Component;

import java.util.List;
import java.util.concurrent.atomic.AtomicInteger;

@Component
public class MyLb implements LoadBalancer {

    private AtomicInteger atomicInteger = new AtomicInteger(0);


    public final int getAndIncrement() {
        int current;
        int next;
        do {
            current = this.atomicInteger.get();
            next = current >= Integer.MAX_VALUE ? 0 : current + 1;
        } while (!this.atomicInteger.compareAndSet(current, next));
        System.out.println("=====>> 当前访问" + next + "此");

        return next;
    }


    @Override
    public ServiceInstance instances(List<ServiceInstance> serviceInstances) {
        int andIncrement = getAndIncrement();
        int index = andIncrement % serviceInstances.size();
        return serviceInstances.get(index);
    }

}
